1. Field of the Disclosure
The present disclosure relates to a display processing apparatus suitable for use with an electronic apparatus, such as, for example, a mobile phone, a personal handyphone system (PHS) set, a personal digital assistant (PDA) device, a portable game machine, a music player device, and a notebook personal computer device. In the present disclosure, when a display magnification ratio, which is an expansion ratio or a reduction ratio, is changed and a display image is displayed, the display magnification ratio is changed by setting the optimal position appropriate for the subject of the display image as the center, and the display image is displayed. As a result, the display magnification ratio of the display image is changed by using the position at which the operator is highly probable to change the display magnification ratio as the center, and the display image is displayed.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2009-187057 describes a display device for performing expansion of a display area and scroll display in response to a touch-panel operation.
In the case of the display device described in Japanese Unexamined Patent Application Publication No. 2009-187057, when a display area is set to an image that is difficult to be fully displayed in the display screen, a partial image, which is an image in the display area, is displayed on a display unit. The display unit is formed as a so-called touch panel. While the finger of the operator is touch-operating the touch panel, the display device performs a process for expanding the display area. When the finger of the operator is moved away from the touch panel, the display device returns the expanded display area to the display area of the size before expansion.
In the display device, when a dragging operation of the operator is detected on the touch panel, the display area is moved in accordance with the movement direction and the movement distance of the finger of the operator in the dragging operation, and thus, the partial image is scroll-displayed.
Furthermore, an example of another related art is a mobile terminal device in which an expansion operation or a reduction operation of a display image is performed by performing a pinch operation on a touch panel.
When a pinch operation is to be performed, the operator causes his/her thumb and index finger in a contact state to be brought into contact with the touch panel. Then, the operator causes the thumb and the index finger in a contact state to be separated from each other while the fingers are in contact with the touch panel. When the mobile terminal device detects the pinch operation of gradually separating the thumb and the index finger in a contact state, the mobile terminal device performs a process for expanding the displayed image at an expansion ratio corresponding to the amount of pinch operation.
Furthermore, the operator causes the thumb and the index finger that are separated from each other to touch the touch panel. Then, the operator gradually decreases the distance between the thumb and the index finger that are separated from each other while the fingers are in contact with the touch panel. When the mobile terminal device detects the pinch operation of gradually decreasing the distance between the thumb and the index finger that are separated, the mobile terminal device performs a process for reducing the displayed image at a reduction ratio corresponding to the amount of pinch operation. Until the displayed image becomes an image of a desired size, the operator repeatedly performs one of the above-mentioned pinch operations.